JP4900367B2 - Development device - Google Patents

Description

  The present invention relates to a developing device.

An electrophotographic image forming apparatus such as a laser printer includes a photosensitive drum on which an electrostatic latent image is formed, and a developing device for developing the electrostatic latent image formed on the photosensitive drum. Yes.
The developing device includes a developing chamber and a toner cartridge that is detachably attached to the developing chamber. Inside the developing chamber, a developing roller and a toner supply roller are rotatably supported in contact with each other. A part of the peripheral surface of the developing roller is exposed from the developing device, and the exposed part is in contact with the surface of the photosensitive drum. The toner cartridge is provided with a stirrer for sending the toner in the toner cartridge to the developing chamber while stirring. The toner supplied from the toner cartridge to the developing chamber is carried on the developing roller via the toner supply roller, and the photosensitive roller is exposed to the electrostatic latent image formed on the photosensitive drum while facing the developing roller. Supplied to the drum.

  As such a developing device, in the unit case of the developing device, a toner supply port and a toner suction port for communicating the developing chamber and the toner cartridge are formed at positions facing both ends in the axial direction of the supply roller. A configuration has been proposed in which an auger member extending along the axial direction of the supply roller is disposed at a position near the toner supply port and the toner suction port (see, for example, Patent Document 1).

In this developing device, the toner supplied into the developing chamber through the toner supply port is conveyed along the axial direction of the auger member, and is supplied to the supply roller during the conveyance. Thus, the toner is uniformly supplied to the supply roller along the axial direction. Further, the toner (deteriorated toner) remaining on the supply roller without being supplied to the developing roller is conveyed along the axial direction of the auger member and returned to the toner cartridge through the toner suction port. Thereby, the toner in the toner cartridge and the deteriorated toner are uniformly mixed, and the quality of the toner is kept uniform.
JP 9-319202 A

  However, in the developing device according to the above proposal, the toner in the toner cartridge is always sent to the developing chamber by the rotation of the stirring member. For this reason, the water level of the toner in the developing chamber is always kept higher than the water level of the toner in the toner cartridge. Since the toner water level in the developing chamber and the toner water level in the toner cartridge are always different, the toner cannot freely move between the developing chamber and the toner cartridge. There is a possibility that it cannot be circulated well.

  Accordingly, an object of the present invention is to provide a developing device that can circulate the developer well.

In order to achieve the above object, the invention according to claim 1 is a developing device, comprising: a developing chamber that provides a developing chamber and a storage chamber for storing a developer supplied to the developing chamber; A developing roller accommodated in the developing chamber and carrying a non-magnetic one-component developer; a supply roller accommodated in the developing chamber for supplying the developer to the developing roller; and accommodated in the storage chamber; The first agitating member that stirs the developer while moving the developer in the rotation direction by rotation in the rotation direction, and the developer providing the developer storage chamber for storing the developer to be supplied to the storage chamber. A developer cartridge, a second stirring member that is housed in the developer housing chamber and stirs the developer in the developer housing chamber, and is provided between the storage chamber and the developer housing chamber; Between the developer storage chamber A wall portion formed so that an opening for circulating the developer faces the storage chamber at a position above the upper end portion of the supply roller, and between the opening of the wall portion and the developer storage chamber. And a conveying member that conveys the developer in the axial direction of the developing roller, the developer accommodating chamber is disposed on a side of the storage chamber, and the conveying member and the opening are arranged in the storage chamber. A transfer chamber disposed below the upper end, storing the transfer member, and having a communication port communicating with the developer storage chamber; and the wall portion includes a portion of the wall of the transfer chamber. The transport chamber communicates with the storage chamber through the opening, and the communication port communicates with the developer storage chamber at least downstream of the opening in the transport direction of the developer by the transport member. It is characterized in that in communication.

A second aspect of the present invention is the auger according to the first aspect, wherein the conveying member has a rotation shaft extending in the axial direction, and conveys the developer by rotation about the rotation shaft. that it is characterized by there.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the first stirring member has a flexible stirring blade, and the opening is formed at a position that interferes with the stirring blade. It is characterized by being.
A fourth aspect of the invention is characterized in that, in the invention of the third aspect , the opening faces downward.

The invention according to claim 5 is the invention according to claim 4 , wherein the transport member transports the developer in one direction of the axial direction, and the opening is a central portion of the transport member in the axial direction. The communication port is formed at a position facing both ends of the transport member in the axial direction.

  According to the first aspect of the present invention, the developing device includes the developing frame. The developing frame is provided with a developing chamber and a storage chamber for storing the developer supplied to the developing chamber. A developing roller and a supply roller are accommodated in the developing chamber. The developer supplied by the supply roller is carried on the developing roller. Moreover, the 1st stirring member is accommodated in the storage chamber. The developer in the storage chamber is stirred while being moved in the rotation direction by the rotation of the first stirring member in a predetermined rotation direction.

Further, a developer storage chamber for storing a developer to be supplied to the storage chamber is formed inside the developer cartridge. A second agitating member is accommodated in the developer accommodating chamber. The developer in the developer storage chamber is stirred by the second stirring member.
A wall portion is provided between the storage chamber and the developer storage chamber. In the wall portion, an opening facing the storage chamber is formed at a position above the upper end portion of the supply roller. Further, a conveying member is arranged between the opening of the wall portion and the developer storage chamber. The developer is transported along the axial direction of the developing roller by the transport member.

Accordingly, when the developer level in the storage chamber becomes lower than the opening of the wall portion with the use of the developing device, the developer in the developer storage chamber is moved by the conveying member to the axis of the developing roller. While being transported in the direction, the storage chamber is replenished through the opening in the wall.
When the developer replenishment from the developer storage chamber to the storage chamber progresses and the water level of the developer in the storage chamber becomes substantially the same as the water level of the developer in the developer storage chamber, the developer is stored through the opening in the wall. The developer circulates between the chamber and the developer storage chamber. That is, the developer in the developer storage chamber is delivered to the transport member while being stirred by the second stirring member. The developer is replenished to the storage chamber through the opening of the wall while being conveyed in the axial direction of the developing roller by the conveying member. On the other hand, the developer in the storage chamber is transferred to the conveying member through the opening of the wall portion by being moved in the rotation direction by the first stirring member. The developer is returned to the developer storage chamber while being conveyed in the axial direction of the developing roller by the conveying member. As a result, the developer can be circulated well between the developer storage chamber and the storage chamber.

Further, the developing device includes a transfer chamber in which a transfer member is accommodated. The transfer chamber has a communication port that communicates with the developer storage chamber. A part of the wall of the transfer chamber is constituted by a wall portion. Further, the transfer chamber communicates with the storage chamber through the opening. As a result, the developer in the developer storage chamber is supplied to the transfer chamber through the communication port, is transferred along the axial direction of the transfer member in the transfer chamber, and is supplied to the storage chamber through the opening of the wall portion. Is done. On the other hand, the developer in the storage chamber is sent to the transfer chamber through the opening in the wall, is transferred along the axial direction of the transfer member in the transfer chamber, and is returned to the developer storage chamber through the communication port. .
According to a second aspect of the present invention, the conveying member is an auger having a rotating shaft extending in the axial direction of the developing roller and conveying the developer by rotation about the rotating shaft. As a result, the developer can be favorably conveyed along the axial direction of the developing roller.

According to the invention described in claim 3 , the first stirring member has a flexible stirring blade. The opening is formed at a position that interferes with the stirring blade. The developer moved in the rotation direction by the rotation of the first stirring member is pushed into the transfer chamber through the opening due to the elasticity of the stirring blade when the stirring blade interferes with the opening. Thereby, the developer near the opening can be surely pushed into the transfer chamber through the opening.

According to invention of Claim 4 , the opening has faced the downward direction. Thereby, the developer in the developer accommodating chamber can be satisfactorily supplied to the storage chamber by free fall.
According to the invention described in claim 5 , the conveying member conveys the developer in one axial direction of the conveying member. The opening is formed at a position facing the central portion of the conveying member in the axial direction. Further, the communication port is formed at a position facing both ends of the conveying member in the axial direction.

  As a result, the developer in the developer storage chamber is fed into the transport chamber through one communication port, and is transported in one axial direction by the transport member. And it is sent to a storage chamber from a conveyance chamber through the formed opening formed in the position facing the center part of the axial direction of a conveyance member. Further, the developer in the storage chamber is fed into the transport chamber through the opening and transported in one axial direction by the transport member. Then, the toner is returned from the transfer chamber to the developer storage chamber via the other communication port. As a result, the developer can be circulated well along such a circulation path.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
1. Overall Configuration of Color Printer FIG. 1 is a side sectional view of a laser printer according to an embodiment of the present invention.
The laser printer 1 includes a main body casing 2. A process cartridge 3 is provided in the main casing 2. The process cartridge 3 is detachably provided in the main casing 2 with the front cover 4 provided on one side wall of the main casing 2 being opened.

In the following description, the side on which the front cover 4 is provided is the front side (front side), and the opposite side is the rear side (back side). Further, when the laser printer 1 is viewed from the front side, the left and right reference is used. Hereinafter, the left-right direction is referred to as the width direction. The process cartridge 3 will be described with reference to a state where the process cartridge 3 is attached to the laser printer 1.
The process cartridge 3 includes a photosensitive drum 5. In the process cartridge 3, a scorotron charger 6, a developing roller 7, a transfer roller 8, and the like are disposed to face the peripheral surface of the photosensitive drum 5.

A scanner unit 9 is disposed above the process cartridge 3.
As the photosensitive drum 5 rotates, the surface of the photosensitive drum 5 is uniformly charged by the scorotron charger 6 and then exposed by the laser beam emitted from the scanner unit 9. As a result, an electrostatic latent image based on the image data is formed on the surface of the photosensitive drum 5. When the electrostatic latent image faces the developing roller 7 as the photosensitive drum 5 rotates, toner is supplied to the electrostatic latent image, and a toner image is formed on the surface of the photosensitive drum 5.

  A paper feed cassette 10 that accommodates the paper P is disposed at the bottom of the main casing 2. The paper P stored in the paper feed cassette 10 is conveyed to a transfer position between the photosensitive drum 5 and the transfer roller 8 by various rollers. The toner image on the surface of the photosensitive drum 5 is transferred onto the paper P by the transfer bias applied to the transfer roller 8 when facing the paper P.

A fixing device 11 is provided behind the process cartridge 3 in the main body casing 2. The sheet P on which the toner image is transferred is conveyed to the fixing device 11. In the fixing device 11, the toner image is fixed on the paper P by heating and pressing. The paper P on which the toner image is fixed is discharged to a paper discharge tray 12 on the upper surface of the main casing 2 by various rollers.
2. Process Cartridge FIG. 2 is a central sectional view of the process cartridge. FIG. 3 is a plan sectional view of the process cartridge.
(1) Overall Configuration of Process Cartridge As shown in FIG. 2, the process cartridge 3 includes a drum cartridge 15 and a developing cartridge 16 as an example of a developing device that is detachably attached to the drum cartridge 15 from the rear. It has.
(1-1) Drum Cartridge The drum cartridge 15 includes a drum frame 20 opened forward. In the drum frame 20, a photosensitive drum 5, a scorotron charger 6 and a transfer roller 8 are provided. The photosensitive drum 5 extends in the width direction and is rotatably held by the drum frame 20. The scorotron charger 6 is disposed at an upper position on the rear side with respect to the photosensitive drum 5. The transfer roller 7 extends in the width direction and is pressed against the photosensitive drum 5 from below.
(1-2) Developing Cartridge The developing cartridge 16 includes a developing frame 21 that is opened rearward and extends in the front-rear direction. The inside of the developing frame 21 is divided into a developing chamber 22 in the rear portion and a storage chamber 23 in the front portion. The developing chamber 22 and the storage chamber 23 are communicated with each other through a developing chamber side communication port 24.

  In the developing chamber 22, a developing roller 7, a supply roller 25, and a layer thickness regulating blade 26 are provided. The developing roller 7 and the supply roller 25 extend in the width direction and are rotatably held by the developing frame 21. A part of the circumferential surface of the developing roller 7 is exposed rearward from the developing frame 21 and is in contact with the circumferential surface of the photosensitive drum 5. The supply roller 25 is in pressure contact with the developing roller 7 from the lower front side behind the developing chamber side communication port 24. The base end portion of the layer thickness regulating blade 26 is fixed to the upper portion in the developing frame 21, and the leading end portion is in pressure contact with the peripheral surface of the developing roller 7.

  The storage chamber 23 contains a non-magnetic one-component positively charged toner (developer). The storage chamber 22 is provided with an agitator 27 as an example of a first stirring member for stirring the toner in the storage chamber 22. The agitator 27 includes an agitator rotating shaft 28 and a flexible stirring blade 29 that rotates around the agitator rotating shaft 28. The stirring blade 29 has a size (the length in the radial direction of the agitator rotating shaft 28) that interferes with an opening 32 formed in the wall 31 of the transfer chamber 30 described below.

  In the developing cartridge 16, a transfer chamber 30 is provided at a position above the front side with respect to the storage chamber 23. The transfer chamber 30 is partitioned by the wall portion 31 and the developing frame 21. In the transfer chamber 30, a transfer auger 35 as an example of a transfer member is provided. As shown in FIG. 3, the transport auger 35 rotates around the auger rotating shaft 40 extending in the width direction and the auger rotating shaft 40, and extends in a spiral shape from one end side to the other end side in the width direction. And auger teeth 41.

  The wall portion 31 extends downward from the upper wall of the developing frame 21, and a lower end portion thereof curves forward and is connected to the front wall of the developing frame 21. The wall portion 31 is disposed at a position above the supply roller 25 in a side view. As shown in FIGS. 2 and 3, an opening 32 that connects the transfer chamber 30 and the storage chamber 23 in the vertical direction is formed in the center portion in the width direction of the wall portion 31.

Further, a toner supply port 33 and a toner suction port 34 as an example of a communication port are formed at both ends in the width direction of the front portion of the transfer chamber 31 (the front wall of the developing frame 21). Specifically, the toner supply port 33 is formed at the left end of the front wall of the developing frame 21. The toner suction port 34 is formed at the right end of the front wall of the developing frame 21.
(1-3) Toner Cartridge The developing cartridge 16 includes a toner cartridge 17 as an example of a developer cartridge that is detachably attached to the developing frame 21 from the rear.

  The toner cartridge 17 is formed in a cylindrical shape extending in the width direction. The internal space of the toner cartridge 17 is a toner storage chamber 18 as an example of a developer storage chamber in which non-magnetic one-component toner is stored. An auger member 36 as an example of a second agitating member for agitating the toner in the toner accommodating chamber 18 is provided in the toner accommodating chamber 18. As shown in FIG. 3, the auger member 36 has auger teeth that extend spirally from one end side in the width direction toward the other end side.

A cartridge side supply port 37 is formed at a position facing the toner supply port 33 of the developing cartridge 16 (conveying chamber 31) at the rear side portion of the toner cartridge 17. Thus, the toner storage chamber 18 and the transfer chamber 20 are communicated with each other via the cartridge side supply port 37 and the toner supply port 33. In the rear portion of the toner cartridge 17, a cartridge side suction port 38 is formed at a position facing the toner suction port 34 of the developing cartridge 16. Thus, the toner storage chamber 18 and the transfer chamber 30 are communicated with each other via the cartridge side suction port 38 and the toner suction port 34.
3. Toner Transport Path FIG. 4 is a schematic cross-sectional view for explaining the toner transport path in a state where the storage chamber is filled with toner. FIG. 5 is a schematic cross-sectional view for explaining a toner conveyance path in a state where toner in the storage chamber is reduced.
(1) Transfer route of toner between the storage chamber and the developing chamber The toner in the storage chamber 23 is agitated in the storage chamber 23 by the rotation of the agitator 27, and a part of the toner is in the developing chamber side communication port 24. To the developing chamber 22. The toner sent to the developing chamber 22 is supplied to the developing roller 7 through the supply roller 25 by contact between the supply roller 25 and the developing roller 7. The toner supplied to the developing roller 7 is regulated by the layer thickness regulating blade 26 as the developing roller 7 rotates, and is carried on the peripheral surface of the developing roller 7 as a thin layer having a constant thickness. Thus, when the electrostatic latent image formed on the circumferential surface of the photosensitive drum 5 faces the developing roller 7, toner is supplied from the developing roller 7 to the electrostatic latent image, and the electrostatic latent image is developed.
(2) Toner transport path in a state where the storage chamber is filled with toner As shown in FIG. 4, in the state where the storage chamber 23 is filled with toner, the upper end of the water level of the toner in the storage chamber 23 is the wall It is located above the opening 32 formed in 31. Further, the toner water level in the storage chamber 23 and the toner water level in the toner storage chamber 18 are substantially the same. In this state, the toner is circulated through the transfer chamber 30 between the storage chamber 23 and the toner storage chamber 18.
(2-1) Toner Transport Path from the Toner Storage Chamber to the Storage Chamber As shown in FIG. 3, the toner in the toner storage chamber 18 moves from the right side to the left side in the toner storage chamber 18 by the rotation of the auger member 36. It is conveyed toward. Then, the cartridge side supply port 37 formed in the left end portion in the rear portion of the toner cartridge 17 and the toner supply port 33 formed in the left end portion in the front portion of the transfer chamber 30 enter the transfer chamber 30. Sent.

The toner sent to the transfer chamber 30 is transferred from the left side to the right side in the transfer chamber 30 by the rotation of the transfer auger 35. And it is sent to the storage chamber 23 through the opening 32 formed in the width direction center part in the rear side part (wall part 31) of the conveyance chamber 30.
(2-2) Transfer route of toner from the storage chamber to the toner storage chamber As shown in FIG. 2, the toner in the storage chamber 23 is rotated in the rotation direction (clockwise direction in FIG. 2) by the rotation of the agitator 27. Moved. Since the stirring blade 29 of the agitator 27 is formed so as to interfere with the opening 32, the toner around the opening 32 in the storage chamber 23 opens due to the interference between the stirring blade 29 and the opening 32 of the agitator 27. 32 is pushed into the transfer chamber 30.

  As shown in FIG. 3, the toner sent to the transfer chamber 30 is transferred from the right side to the left side in the transfer chamber 30 by the rotation of the transfer auger 35. The inside of the transfer chamber 30 is passed through the toner suction port 34 formed at the right end portion of the front portion of the transfer chamber 30 and the cartridge side suction port 38 formed at the right end portion of the rear portion of the toner cartridge 17. The toner is sent into the toner storage chamber 18.

As a result, the toner is circulated through the transfer chamber 30 between the storage chamber 23 and the toner storage chamber 18.
(3) Toner transport path in a state where the toner in the storage chamber is reduced As shown in FIG. 5, in the state where the toner in the storage chamber 23 is reduced, the upper end of the water level of the toner in the storage chamber 23 is directed to the wall portion 31. It is located below the formed opening 32. In this state, the toner in the toner storage chamber 18 is supplied to the storage chamber 23 via the transfer chamber 30.

  As shown in FIG. 3, the toner in the toner storage chamber 18 is conveyed from the right side to the left side in the toner storage chamber 18 by the rotation of the auger member 36. The inside of the toner storage chamber 18 is passed through a cartridge side supply port 37 formed at the left end portion of the rear portion of the toner cartridge 17 and a toner supply port 33 formed at the left end portion of the front portion of the transfer chamber 30. The toner is sent into the transfer chamber 30.

The toner sent to the transfer chamber 30 is transferred from the left side to the right side in the transfer chamber 30 by the rotation of the transfer auger 35. And it is sent to the storage chamber 23 by free fall through the opening 32 formed in the rear side part (wall part 31) of the transfer chamber 30. As a result, the toner in the toner storage chamber 18 is supplied to the storage chamber 23 via the transfer chamber 30.
4). As described above, the process cartridge 3 includes the developing frame 21. The developing frame 21 is provided with a developing chamber 22 and a storage chamber 23 for storing toner supplied to the developing chamber 22. The developing chamber 22 accommodates the developing roller 7 and the supply roller 25. The developing roller 7 carries toner supplied by the supply roller 25. An agitator 27 is accommodated in the storage chamber 23. The toner in the storage chamber 23 is agitated while being moved in the rotation direction by the rotation of the agitator 27 in a predetermined rotation direction.

A toner cartridge 17 is disposed on the side of the storage chamber 23. Inside the toner cartridge 17, a toner storage chamber 18 that stores toner to be supplied to the storage chamber 23 is formed. An auger member 36 is accommodated in the toner storage chamber 18. The toner in the toner storage chamber 18 is agitated by the auger member 36.
A wall 31 is provided between the storage chamber 23 and the toner storage chamber 18. In the wall portion 31, an opening 32 facing the storage chamber 23 is formed at a position above the upper end portion of the supply roller 25. A transport auger 35 is disposed between the opening 32 of the wall portion 31 and the toner storage chamber 18. The toner is transported along the axial direction of the developing roller 7 by the transport auger 35.

Thereby, when the water level of the toner in the storage chamber 23 becomes lower than the opening 32 of the wall portion 31 as the process cartridge 3 is used, the toner in the toner storage chamber 18 is transferred to the transport auger 35. Thus, while being conveyed in the axial direction of the developing roller 7, the storage chamber 23 is replenished through the opening 32 of the wall portion 31.
When the toner supply from the toner storage chamber 18 to the storage chamber 23 progresses and the water level of the toner in the storage chamber 23 and the water level of the toner in the toner storage chamber 18 become substantially the same, the opening 32 of the wall portion 31. Through, the toner circulates between the storage chamber 23 and the toner storage chamber 18. That is, the toner in the toner storage chamber 18 is transferred to the transporting oven 35 while being agitated by the auger member 36. Then, the toner is replenished to the storage chamber 23 through the opening 32 of the wall portion 31 while being transported in the axial direction of the developing roller 7 by the transport auger 35. On the other hand, the toner in the storage chamber 23 is transferred to the transport auger 35 through the opening 32 of the wall 31 by being moved in the rotational direction by the agitator 27. Then, the toner is returned to the toner storage chamber 18 while being transported by the transport auger 35 in the axial direction of the developing roller 7. As a result, the toner can be circulated favorably between the toner storage chamber 18 and the storage chamber 23.

The transport auger 35 has an auger rotating shaft 40 extending in the axial direction of the developing roller 7 and is an auger that transports toner by rotation about the auger rotating shaft 40. Thereby, the toner can be favorably conveyed along the axial direction of the developing roller 7.
Further, the process cartridge 3 includes a transfer chamber 30 in which the transfer auger 35 is accommodated. The transfer chamber 30 has a cartridge side supply port 37 and a cartridge side suction port 38 that communicate with the toner storage chamber 18. A part of the wall of the transfer chamber 30 is constituted by a wall portion 31. In addition, the transfer chamber 30 communicates with the storage chamber 23 through the opening 32. As a result, the toner in the toner storage chamber 18 is supplied to the transfer chamber 30 via the cartridge side supply port 37, and is transferred along the axial direction of the transfer auger 35 in the transfer chamber 30. It is supplied to the storage chamber 23 via 32. On the other hand, the toner in the storage chamber 23 is sent to the transfer chamber 30 through the opening 32 of the wall portion 31, and is transferred along the axial direction of the transfer auger 35 in the transfer chamber 30, and passes through the cartridge side suction port 38. Through the toner storage chamber 18.

  Further, the agitator 27 has a flexible stirring blade 29. The opening 32 is formed at a position that interferes with the stirring blade 29. The toner moved in the rotation direction by the rotation of the agitator 27 is pushed into the transfer chamber 30 through the opening 32 due to the elasticity of the stirring blade 29 when the stirring blade 29 interferes with the opening 32. As a result, the toner near the opening 32 can be reliably pushed into the transfer chamber 30 through the opening 32.

The opening 32 faces downward. Thereby, the toner in the toner storage chamber 18 can be replenished to the storage chamber 23 by free fall.
Further, the transport auger 35 transports the toner in one axial direction of the transport auger 35. The opening 32 is formed at a position facing the central portion of the transport auger 35 in the axial direction. Further, the cartridge side supply port 37 and the cartridge side suction port 38 are formed at positions facing both ends of the transport auger 35 in the axial direction.

Thus, the toner in the toner storage chamber 18 is sent into the transfer chamber 30 through the cartridge side supply port 37 and is transferred from the right side to the left side along the axial direction by the transfer auger 35. And it is sent to the storage chamber 23 from the conveyance chamber 30 through the opening 32 formed in the position facing the central part of the axial direction of the conveyance auger 35. Further, the toner in the storage chamber 23 is sent into the transfer chamber 30 through the opening 32 and is transferred from the right side to the left side along the axial direction by the transfer auger 35. Then, the toner is returned from the transfer chamber 30 to the toner storage chamber 18 through the cartridge side suction port 38. As a result, the toner can be circulated well along such a circulation path.
5. Second Embodiment FIG. 6 is a central sectional view of a process cartridge according to a second embodiment of the present invention. FIG. 7 is a plan sectional view of a process cartridge according to the second embodiment of the present invention. FIG. 8 is a schematic cross-sectional view for explaining a toner conveyance path in a state where the storage chamber is filled with toner in the process cartridge according to the second embodiment of the present invention. FIG. 9 is a schematic cross-sectional view for explaining a toner transport path in a state where the toner in the storage chamber is reduced in the process cartridge according to the second embodiment of the present invention. 6 to 9, parts corresponding to the parts shown in FIGS. 2 to 5 are denoted by the same reference numerals as those of the parts, and the description of the parts is omitted.
Storage chamber In the process cartridge 3 shown in FIG. 2, the transfer chamber 30 is partitioned by the wall portion 31 and the developing frame 21 at a position above the front side of the storage chamber 23, but in the process cartridge 51 shown in FIG. 6, The transfer chamber 30 and the wall portion 31 are omitted.

A portion of the front wall of the developing frame 21 that faces the storage chamber 23 forms a first wall portion 52 as an example of a wall portion. In the first wall portion 52, a development side opening 53 as an example of an opening penetrating the first wall portion 52 in the front-rear direction is formed at a position above the upper end portion of the supply roller 25. As shown in FIG. 7, the development-side opening 53 is located at a substantially central portion in the width direction of the development frame 21.
(2) Toner Cartridge In the toner cartridge 17, a transport chamber 54 is provided at an upper position on the rear side. The transfer chamber 54 is partitioned by a second wall portion 55 and a partition wall 56 as an example of a wall portion. In the transfer chamber 54, a transfer auger 61 as an example of a transfer member is provided. As shown in FIG. 7, the transport auger 61 rotates in the width direction and rotates around the auger rotation shaft 62, and extends in a spiral shape from one end side to the other end side in the width direction. It has auger teeth 63.

  The second wall portion 55 is constituted by a rear upper portion of the toner cartridge 17 and forms a wall portion 57 in cooperation with the first wall portion 52 of the developing cartridge 16. In the second wall portion 55, a cartridge side opening 58 as an example of an opening is formed at a position facing the developing side opening 53 of the first wall portion 52. As a result, the transfer chamber 54 and the storage chamber 23 communicate with each other in the front-rear direction via the developing side opening 53 and the cartridge side opening 58.

The partition wall 56 extends downward from the upper wall of the toner cartridge 17, and the lower end of the partition wall 56 is curved backward to be connected to the front wall of the toner cartridge 17. At both ends in the width direction of the partition wall 56, a toner supply port 59 and a toner suction port 60 as examples of communication ports are formed so as to penetrate the partition wall 56 in the vertical direction. Specifically, the toner supply port 59 is formed at the left end of the partition wall 56. The toner suction port 60 is formed at the right end of the partition wall 56. As a result, the transfer chamber 54 and the toner storage chamber 18 communicate with each other in the vertical direction via the toner supply port 59 and the toner suction port 60.
(3) Toner transport path (3-1) Toner transport path in a state where the storage chamber is filled with toner As shown in FIG. 8, in the state where the storage chamber 23 is filled with toner, The upper end of the water level of the toner is from a developing side opening 53 and a cartridge side opening 58 (hereinafter simply referred to as “openings 53, 58”) formed in the wall portion 57 (the first wall portion 52 and the second wall portion 55). Is also located on the upper side. In this state, the toner is circulated through the transfer chamber 54 between the storage chamber 23 and the toner storage chamber 18.
(3-1-1) Toner Transport Path from the Toner Storage Chamber to the Storage Chamber As shown in FIG. 7, the toner in the toner storage chamber 18 is moved from the right side in the toner storage chamber 18 by the rotation of the auger member 36. It is conveyed toward the left side. Then, the toner in the toner storage chamber 18 is sent into the transfer chamber 54 through the toner supply port 59 formed at the left end of the partition wall 56 of the toner cartridge 17.

The toner sent to the transfer chamber 54 is transferred from the left side to the right side in the transfer chamber 54 by the rotation of the transfer auger 61. Then, the toner in the transfer chamber 54 is sent to the storage chamber 23 through the openings 53 and 58 formed in the wall portion 57 of the transfer chamber 54.
(3-1-2) Transfer route of toner from the storage chamber to the toner storage chamber The toner in the storage chamber 23 is sent to the transfer chamber 54 through the openings 53 and 58 by the rotation of the agitator 27.

The toner sent to the transfer chamber 54 is transferred from the right side to the left side in the transfer chamber 54 by the rotation of the transfer auger 61. Then, the toner in the transfer chamber 54 is sent into the toner storage chamber 18 through the toner suction port 60 formed at the right end of the partition wall 56 of the transfer chamber 54.
As a result, the toner is circulated between the storage chamber 23 and the toner storage chamber 18 via the transfer chamber 54.
(4) Toner Conveying Route in a State in which the Toner in the Reservoir is Reduced As shown in FIG. 9, in a state in which the toner in the storage chamber 23 is reduced, the upper end of the toner level in the storage chamber 23 is directed to the wall portion 57. It is located below the formed openings 53 and 58. In this state, the toner in the toner storage chamber 18 is replenished to the storage chamber 23 via the transfer chamber 54.

As shown in FIG. 7, the toner in the toner storage chamber 18 is conveyed from the right side to the left side in the toner storage chamber 18 by the rotation of the auger member 36. Then, the toner in the toner storage chamber 18 is sent into the transfer chamber 54 through the toner supply port 59 formed at the left end of the partition wall 56 of the toner cartridge 17.
The toner sent to the transfer chamber 54 is transferred from the left side to the right side in the transfer chamber 54 by the rotation of the transfer auger 61. Then, the toner in the transfer chamber 54 is sent to the storage chamber 23 through the openings 53 and 58 formed in the wall portion 57 of the transfer chamber 54. As a result, the toner in the toner storage chamber 18 is supplied to the storage chamber 23 via the transfer chamber 54.
(5) Effects The same effects as those of the process cartridge 3 shown in FIGS. 2 to 5 can be obtained by the configuration of the process cartridge 51 shown in FIGS.

FIG. 1 is a side sectional view of a laser printer according to an embodiment of the present invention. FIG. 2 is a central sectional view of the process cartridge. FIG. 3 is a plan sectional view of the process cartridge. FIG. 4 is a schematic cross-sectional view for explaining a toner transport path in a state where the storage chamber is filled with toner. FIG. 5 is a schematic cross-sectional view for explaining a toner conveyance path in a state where toner in the storage chamber is reduced. FIG. 6 is a central sectional view of a process cartridge according to the second embodiment of the present invention. FIG. 7 is a plan sectional view of a process cartridge according to the second embodiment of the present invention. FIG. 8 is a schematic cross-sectional view for explaining a toner conveyance path in a state where the storage chamber is filled with toner in the process cartridge according to the second embodiment of the present invention. FIG. 9 is a schematic cross-sectional view for explaining a toner transport path in a state where the toner in the storage chamber is reduced in the process cartridge according to the second embodiment of the present invention.

Explanation of symbols

3 Process Cartridge 7 Developing Roller 17 Toner Cartridge 18 Toner Storage Chamber 22 Developing Chamber 23 Storage Chamber 25 Supply Roller 27 Agitator 29 Stirrer 30 Transport Chamber 31 Wall 32 Opening 33 Toner Supply Port 34 Toner Suction Port 35 Transfer Auger 36 Auger Member 37 Cartridge side supply port 38 Cartridge side suction port 40 Auger rotation shaft 52 First wall portion 53 Development side opening 54 Transport chamber 55 Second wall portion 57 Wall portion 58 Cartridge side opening 59 Toner supply port 60 Toner suction port 61 Transport auger 62 Auger Axis of rotation

Claims (5)

A developing frame providing a developing chamber and a storage chamber for storing a developer supplied to the developing chamber;
A developing roller housed in the developing chamber and carrying a non-magnetic one-component developer;
A supply roller housed in the developing chamber for supplying a developer to the developing roller;
A first stirring member that is housed in the storage chamber and stirs the developer while moving the developer in the rotation direction by rotation in a predetermined rotation direction;
A developer cartridge for providing therein a developer storage chamber for storing a developer to be supplied to the storage chamber;
A second agitating member accommodated in the developer accommodating chamber and agitating the developer in the developer accommodating chamber;
An opening provided between the storage chamber and the developer storage chamber for circulating the developer between the storage chamber and the developer storage chamber is located above the upper end of the supply roller. A wall formed to face the storage chamber;
A transport member that is disposed between the opening of the wall and the developer storage chamber and transports the developer in the axial direction of the developing roller;
The developer storage chamber is disposed on a side of the storage chamber ,
The conveying member and the opening are disposed below the upper end of the storage chamber,
A transport chamber that houses the transport member and has a communication port communicating with the developer storage chamber;
The wall portion constitutes a part of the wall of the transfer chamber,
The transfer chamber communicates with the storage chamber through the opening,
The developing device, wherein the communication port communicates with the developer accommodating chamber at least downstream of the opening in the developer conveying direction by the conveying member .   The developing device according to claim 1, wherein the conveying member is an auger having a rotating shaft extending in the axial direction, and conveying the developer by rotation about the rotating shaft. The first stirring member has a flexible stirring blade,
Said opening is formed in a position interfering with said stirring blades, a developing device according to claim 1 or 2. The developing device according to claim 3 , wherein the opening faces downward. The conveying member conveys the developer in one direction of the axial direction;
The opening is formed at a position facing the central portion of the transport member in the axial direction,
The developing device according to claim 4 , wherein the communication port is formed at a position facing both ends of the transport member in the axial direction.

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